Engineering & Works

GREENFLOOR® Idéale Atmosphère® is a VINCI Energies patented and innovative system that ensures building’s heating and cooling using a single media: the air.

The Greenfloor system was developed in 2012 at LEFORT FRANCHETEAU, a member of BUILDING Solutions. A life-size demonstrator was built in partnership with LAINE DELAU at La Garenne-Colombes: two floors of office space designed using the “box-in-a-box” principle. This allows the creation of extreme weather conditions around a building for technical validation. Validation took several years of testing to design the operating system and understand the effects of inertia. The process is patented in France and Europe and was awarded the VINCI Innovation Prize in 2015.

In a nutshell, the Greenfloor system is comprised of a network of small-diameter ducts embedded in the building’s concrete slabs. Hot or cold air is circulated throughout the premises and insure the air conditioning. That’s the first advantage: no more hydraulic networks. Only one fluid remains on-site: air. The concrete slabs work like cooling or heating batteries: charging in positive or negative calories that are then released with a delay effect. That’s the second advantage: the concrete slab heats up or cools down, depending on inertia. It is then possible to flatten production curves by “charging” slabs at night, avoiding peak oversizing, while generating energy-savings. Lastly, thermal diffusion is mainly accomplished thanks to the slab’s radiating effect, bringing even more comfort as it avoids the need for forced-air heating.

In summary, this innovation makes it possible to optimize a building, its occupants’ comfort and the energy performance of an entire facility, at competitive installation and operating costs.

Find out more about the Greenfloor project at the MERELEC site in Beauvais

This first-ever GREENFLOOR commercial project was made possible thanks to the support of VINCI Energies.

400 m² have ducts incorporated directly into the concrete slab floors – instead of the ceilings – because the building is a one-story edifice. The developer was convinced after checking out the demonstrator. VINCI Energies proposed a co-contracting project with SOGEA Picardie, to optimize interface management between structural and technical lots. It was this specific organization that was chosen.

“The premises are heated or cooled without anyone noticing: there’s no noise, no air streams, everything is automatic and yet temperatures are stable and homogenous” said Stéphane Kegelart, CEO of MERELEC. “The atmosphere is healthier, thanks to increased air exchange. Too bad the first floor wasn’t equipped with the same system!”

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